Subbed photographically sensitive film element



Jan. 8, 1963 A. R. A. BEEBER ETAL 3,072,432

SUBBED PHOTOGRAPHICALLY SENSITIVE FILM ELEMENT Filed Jan. 10, 1958 GELATIN, AgX EMULSION 65 L ATIN SUBBING PVM MA CE LLULOSE ACE TA TE v ICHROMATED COLLOID, AgX GELATIN SUBBING 23 PVM/MA m 2 CELLULOSE NITRATE 24 TRACING CLOTH 3! /GELATIN, AgX EMULSION 32 GELATIN SUBBING CELLULOSE ESTER, PVM/MA POLYETHYLENE TEREPHTHALATE aamruv, AgX EMULSION .ri GELATl/V-PVM/MA SUBB/NG 48 AL/(YD RESIN 44 cuss man/c IMPREGNATED WITH poussrzn RESIN I E CELLULOSE ESTER, SAPONlF/ED a COATED 55 WITH 0/420 COMPOUND -lgl l lm.lll 5 051.4 TIN SUBB/NG I 54 TRANSPARENT/ZED PAPERV BINDER, FERRIC $41.7; SILVER NIT/Mr:

cELu/LosE ESTER, PVM/MA MPOLYETHYLENE TEREPHTHALATE INVHVTOR. ALLAN R.A. BEEBER y JAROMIR KOSAR AT TORNEY United States Pate-ntO 3,072,482 SUBBED PHOTOGRAPHICALLY SENSITIVE FILM ELEMENT Allan R. A. Beeber, Elizabeth, N.J., and Jaromir Kosar,

Beechhurst, N.Y., assignors to Keufiel & Esser Company, Hoboken, N.J., a corporation of New Jersey Filed Jan. 10, 1958, Ser. No. 708,278

Claims. (Cl. 9675) This invention relates to subbing or anchoring layers for use in photosensitive materials. Such layers are used for example in order to anchor a photographic emulsion or the liketo a base sheet. More specifically the invention relates to subbing or anchoring layers including methyl vinyl ethermaleic anhydride polymer or its esters.

As is known in the art it is ordinarily necessary in the manufacture of photosensitive materials to make use of subbing or anchoring layers in order to aflix a photosensitive layer to a suitable support or base sheet. In the case of ordinary photographic film for example, the supportisusually prepared from a cellulose derivative such as cellulose nitrate, cellulose acetate, and other cellulose esters such as cellulose propionate, cellulose butyrate, cellulose acetate-propionate, cellulose acetate-butyrate and the like. Ethers of cellulose, such as methyl ether, {ethyl ether and the like are also used. Other types of films such as polyethylene terephthalate film which may be orientated orunor-ientated are also used in the preparationofphotosensitive materials. Woven glass fabrics impregnated with a polyester resin or polystyrene have also ,been used. In addition, tracing cloth, transparentizedfl papers such astracing, paper and ordinary paper are used, as base materials for photosensitive coatings. All of these base materials other than ordinary paper are hydrophobic.

- Themanner of, securing the proper adhesion of photosensitive layers to the various types of hydrophobic base materials, constitutes a serious problem. However, the problem is not one of simple adhesion since many compounds known as adhesives are not satisfactory for producing anchorage, The degree of adhesion of the layers to the base must be neither too great, in which case the resulting film is brittle, nor too slight, in which case the layers of the film strip or peel from the support. In most cases. the support is hydrophobic and when some hydrophilic substance,'such as gelatin is coated onto a hydro phobic base, it is found that there is little or no adhesion between the two. As a matter of fact, a hydrophilic layer can be peeled from such asupport with complete ease.

Thus, in the preparation of photosensitive materials, it is .very often necessary to permanently affix a waterpermeable colloid layer to a hydrophobic support. In

order to secure adequate adhesion between the photo,- sensitive layer and the support, it is necessary to impart .a hydrophilic nature to the surface of the base sheet. This is accomplished by treating the base sheet with what is known as a subbing solfution. Ordinarily, the sub bing material should be soluble or dispersible in a solvent which will dissolve or soften the surface to be coated. This will help to anchor the subbing material to the surface of the base sheet. The subbing material should also form a coating free from tackiness so that the subbed material can be rolled and stored prior'to the application of further coatings. sist-ant to stripping when dry or when soaked in water. The subbing layer should bewater-permeable, free from color and transparent and it should not desensitize or artificially age the photosensitive layer. In the past, hydrophobic base materials for photosensitivelayers have been coated with gelatin dispersions in organic solvents such as ethyl alcohol, acetone, ethyl The subbing layer should be re.'

Patented Jan. 8, 1963 acetate and mixtures of these solvents. However, in many cases the adherence was not satisfactory and the top-layer could be flaked oif by flexing the base sheet.

Now it has been found that the addition of vinyl methyl ether-maleic anhydride polymer or its esters to the coating system improves the anchoring properties considerably. For example a hydrophobic base sheet can be coated with a solution of vinyl methyl ether-maleic anhydride polymer and then after this treatment, the base material is coated with a conventional gelatin subbing solution and finally with a photographic emulsion. For this purpose the vinyl methyl ether-maleic anhydride polymer may be dissolved in alcohols, ketones, acetates or mixtures of these solvents. The solution should contain at least 0.1 percent and no more than 10 percent of the vinyl methyl ether-maleic anhydride polymer or its esters.

Another way of practicing the invention is to coat the base sheet with a synthetic resin solution containing at least 0.01 percent and no more than 10 percent of vinyl methyl ether-maleic anhydride polymer or its esters, following this with a gelatin subbing and a photographic emulsion. The synthetic resin may for example be a cellulose ester, an alkyd resin or the like.

A third way is to coat the base sheet with a gelatin subbing solution including no less than 0.01 percent and no more than ,5 percent of vinyl methyl ethermaleic anhydride polymer orits esters, coating the usual photographic emulsion upon the base sheet subbed in this manner.

' Vinyl methyl ether-maleic anhydride polymer is com.- monly referred to as PV M/ MA.

The application of thevarious layers to the base sheet may be carried out in any known manner. The base material is coated with one of the solutions described and after this coating has dried, it is followed by the next layer to be used. The sensitive emulsion layer is finally coated over the subbing layers.

The objects of the invention discussed above and the means for their attainment will be better understood after reading the following description taken in connection with the accompanying drawing in which: FIG; I is -a view in enlarged diagrammatic section of the photosensitive materal described in Example I.v

FIG. II is a view in enlarged diagrammatic section of the photosensitive material described in Example II.

FIG. III is a view in enlarged diagrammatic section of the photosensitive material described in Example III.

FIG. IV is a view in enlarged diagrammatic section of thephotosensitive .materal described inExample IV.

FIG. V is a view in enlarged diagrammatic section of the photosensitive material described in Example V.

FIG. VI is a view in enlarged diagrammatic section of the photosensitive material described .in'Example VI.

Example I As illustrated in FIG. I the base material of cellulose acetate is coated with 2% solution of polyvinyl methyl ether-maleic anhydride in a mixture of ethyl alcohol and acetone. The resulting layer 3 is dried for about two minutes at about 150 F. The polymer layer is then coated with a gelatin subbing layer 2 consisting of a 1% gelatin solution in a mixture of 50% ethyl alcohol and 50% acetone. A silver halide emulsion layer 1 is coated on this gelatin subbing layer. The photosensitive material produced in this manner exhibits excellent adhesion Parts Gelatin 1.0 Water 5.0 Salicylic acid- 0.8 Methyl alcohol 75.0 Acetone 225.0

This forms the layer 22. A bichromated colloid layer 21 including a silver halide is coated on this subbing layer. The anchorage of the colloid layer to the base material in this photosensitive material is excellent when the material is wet or dry. The subbing layers have no adverse effect upon the photosensitive layer. As is known in the art, this type of photosensitive layer is developed after exposure to ultraviolet light by washing off the unexposed areas and blackening the remaining image areas with a conventional silver halide developer.

This type of bichrornated colloid photosensitive layer may be applied over some of the combinations of layers disclosed in the other examples and figures of the drawing. However, this type of layer does not coat well directly on a layer which contains PVM/MA. It may be coated readily over a conventional gelatin subbing layer which has been applied over other layers which may include PVM/ MA.

Example III As shown in FIG. HI a polyethylene terephthalate film 34 is coated with a mixture of cellulose nitrate and the butyl ester of vinyl methyl ether-maleic anhydride copolymer of the following composition:

Nitrocellulose 14.0 Ethyl alcohol 1400.0 Cellosolve 45.0 PVM/MA-butyl ester 98.0

Example IV As shown in FIG. IV the base material 44 consisting of glass fabric impregnated with a polyester resin is coated with a discrete layer of alkyd resin 48 and subbed with a gelatin solution of the following composition:

Percent Gelatin 1 Water 2 Acetic acid Ethyl alcohol.. 45 10% solution of butyl ester of PVM/MA 5 Acetone 37 This forms the subbing layer 47. A gelatin silver halide emulsion is coated directly onto the subbing layer 47 and the resulting emulsion layer 41 is dried. The emulsion layer has excellent wet and dry adherence to the base material by virtue of the anchoring substratum. The substratum does not cause any desensitization or artificial aging of the gelatin silver halide emuls'on.

Example V As shown in FIG. 5 the base material consisting of transparentized paper 54 is subbed with a conventional gelatin subbing solution 52 as described in Example III. The material is then coated with a 5% solution of polyvinyl methyl ether-maleic anhydride in methyl alcohol to form a layer 53. After drying for about 1 minute at F., a cellulose acetate layer is coated thereon. This layer is saponified by a caustic solution and sensitized with a diazotype solution of the following composition:

Grams Diazo diethyl aniline 50 Citric acid 60 Boric acid 20 Resorcinol 25 Thiourea 20 ZnCl 10 Water, up to 4000 cc.

The upper three layers of this example may also be applied over a glass fabric base impregnated with a polyester resin which has been coated with an alkyd resin or over a polyethylene terephthalate base sheet which has been coated with a layer containing a cellulose ester and PVM/ MA.

Example VI As shown in FIG. VI a polyethylene terephthalate film 64 is coated with a mixture of cellulose nitrate and the butyl ester of vinyl methyl ether-maleic anhydride copolymer. This subbing layer 63 is then coated with a brownprint sensitizing emulsion of the following composition:

This forms the light sensitive layer 62. The ferric salts and tartaric acid are dissolved in water and a solution of silver nitrate is added very slowly under constant stirring. Then the Rhoplex WN 75 and Elvacet are added.

The anchorage of the sensitizing layer to the support is excellent whether the material is wet or dry.

Various solvents may be used in the gelatin subbing compositions and these solvents may be chosen according to their action on the base material. For example, when a cellulose acetate base is used a low molecular weight alcohol or a ketone or a mixture of alcohol and ketone may be employed. The ratio of alcohol to ketone ranges from about 50-50% to 75-25%, 'espectively. When the base material is cellulose acetate-propionate film, an alkyd ester, such as, for example methyl acetate, ethyl acetate, butyl acetate and the like may be effectively employed. In general a Wide variety of organic solvents or solvent mixtures may be used for the various base materials so long as the solvent wets or attacks the surface of the base material, i.e. the base is somewhat soluble in an organic solvent or organic solvent mixture. Since the materials suitable for base materials and their solvent properties are known, a person skilled in the art would have no difficulty in selecting a suitable solvent or solvent combination for use in the subbing composition.

As shown by the examples, the subbings including polyvinyl methyl ether-maleic anhydride or its esters are not necessarily used alone but may if desired be used in conjunction with conventional subbing layers such as gelatin, water-sensitive cellulose esters, water-proofing layers and filter layers. It is also possible to incorporate anti-halation dyes in some of these layers.

As shown in the examples, the invention is not limited tosilver halide as the light sensitive material since other types of light sensitive materials may also be used. For example, the light sensitive material may be a bichromated hydrophilic colloid such as, gelatin, glue, gum arabic or polyvinyl alcohol sensitized with potassium bichromate or a diazido compound. These layers may or may not also include a silver halide salt as a pigment. Light sensitive ferric salts as used in blueprint paper or in brownprint paper in combinatoin with silver salts other than halides may also be used as the light sensitive material. Diazo compounds with or without a coupling component may also be used. When the diazo com-. pounds are used, the sensitivity of the binding or subbing layer to water may be less critical. For example in this case polyvinyl acetate or a cellulose acetate may be used as the binder. The light sensitive layer may also consist of a polymerizable vinyl compound and a photoreducible dye as described in the article by Gerald Oster.

in Photographic Engineering, vol. 4, No. 3, pages 173- 178 (1953).

Having thus described the invention, what is claimed 2. The photosensitive material according to claim 1 in which the hydrophobic layer is cellulose acetate providing a base in bonded contact with said thin layer.

3. The photosensitive material according to claim 1 in which the hydrophobic layer is cellulose nitrate and the hydrophobic layer is coated on a base of tracing cloth.

4. The photosensitive material according to claim 1 in which the hydrophobic layer is a cellulose ester and the hydrophobic layer is coated on a base of polyethylene terephthalate.

5. The photosensitive material according to claim 1 in which the hydrophobic layer is an alkyd resin and is coated on a base of glass fabric impregnated with a polyester resin.

6. The photosensitive material according to claim 1 in which the gelatin layer is coated on a base of transparentized paper.

7. The photosensitive material according to claim 1 in which the gelatin layer is in direct bonded contact with transparentized paper base, and said hydrophobic layer is cellulose acetate, said cellulose acetate having its outer surface saponified and said photosensitive component being a diazo compound incorporated in said outer saponified surface of said cellulose acetate.

8. The photosensitive material according to claim 1 in which the thin layer includes gelatin.

9. The photosensitive material according to claim 1 in which the hydrophobic material is a cellulose ester and the cellulose ester hydrophobic layer is in bonded contact with a base.

10. The photosensitive material according to claim 1 in which the thin layer includes a cellulose ester.

References Cited in the file of this patent UNITED STATES PATENTS Eichorn Aug. 14, 1958 

1. A PHOTOSENSITIVE MATERIAL COMPRISING A THIN LAYER HAVING AS AN ESSENTIAL COMPONENT AT LEAST ONE COMPONENT FROM THE GROUP CONSISTING OF POLYVINYL METHYL ETHERMALEIC ANHYDRIDE AND ITS ESTERS, AN ORGANIC SOLVENT SOLUBLE HYDROPHOBIC LAYER IN DIRECT BONDED ADHERENT CONTACT WITH ONE SIDE OF SAID THIN LAYER, A GELATIN LAYER IN DIRECT BONDED CONTACT WITH THE OTHER SIDE OF SAID THIN LAYER AND A PHOTOSENSITIVE COMPONENT CARRIED BY ONE OF THE OUTERMOST LAYERS OF SAID PHOTOSENSITIVE MATERIAL.
 7. THE PHOTOSENSITIVE MATERIAL ACCORDING TO CLAIM 1 IN WHICH THE GELATIN LAYER IS IN DIRECT BONDED CONTACT WITH TRANSPARENTIZED PAPER BASE, AND SAID HYDROPHOBIC LAYER IS CELLULOSE ACETATE, SAID CELLULOSE ACETATE HAVING ITS OUTER SURFACE SAPONIFIED AND SAID PHOTOSENSITIVE COMPONENT BEING A DIAZO COMPOUND INCORPORATED IN SAID OUTER SAPONIFIED SURFACE OF SAID CELLULOSE ACETATE. 